Device for testing fiber board



' 'J 'w. WEBB DEVICE FOR TESTING FIBER BOARD Apr, l24, 19.23.

Filed Feb. 28 1921 L, EL.

Patented Apr. 24, 1923.

DEVICE Foa TESTING, FIBER Boeien. 1

Application led February 28,. 1921.'. Serial No. 448,439.

To a/ZZ whomz't may concern: f

' Be it known that I, JOHN W. VEBB, .a citizen of the United States, residing at Chr cago, in the county of Cook and State of 5 Illinois, have invented certainnew and useful Improvements in 'Devices for Testing Fiber Board, of which the following isa specification. i I My invention relates to a simple paper board testing device which in some respects may vbe regarded as an improvement upon the device disclosed in Patent No. 1,328,349, ,A issued to W'ebb Tester, Incorporated, on

January th, 1920, for improvements 1n de- 15 vices for testing corrugated paper board and corrugated paper board boites.l The object of my invention is thek provision. of a portable pocket tool of soiiiewhatsi'milar design, i more particularly adapted for measuring the 20 bursting strength of relatively heavy fiber board and paste board or paper of ysubstan- 'tial strength and thickness, and which-will y also measure the thickness of the board in "if" adjusting the tool` for making a test of v its bursting strength.` `VVith the vforegoing and incidental objects and advantages relating toj 'the construction of the tool `in view, 'I have invented the'novel testingdevice shown in the accompanying drawings and herein'- after described with reference` thereto in detail, the essential elements of my invention being more particularly pointed out in the appended claims. f y .A

l Figure 1 of the drawing shows mynovel r testing'y device in elevation; Fig. 2 i's a central longitudinal section oi. the same, the

plane ofthe section being ata right angle tothe positionfoic thehtool as shown ini Fig. 1; Fig. 3 is an enlarged section corresppn-ding to the upper portionof Fig. 2.; Fig. i isv anv enlarged fragmentary sectiony showing the construction of the plunger headand adjacent portions ofthe tool; Fig. 5 isa detail showing the split spring for yieldingly sition; and Figs. 6 and 7 laresections on the lines 6-6 and 74-7, respectively, otFig; 2 looking in the direction ofthe arrow.y

The saine: reference characters indicat'ethe y tested, anda sb ank secured thereto and housretaining the sliding indicating' collar in poing a spring-pressed plunger adapted to be put under'-increasingtension by a `rotatable sleeve until the stress of the spring (indicated by a scale on vthe shank) causes the f Y' plunger to burstthrough the paper. Proceeding to a descriptioiiof the specific construction o'f my new tester, the shank 1 of the device is screw'threaded, or secured in any suitable manner to a transversely slotted baseblock 2'which latter consists of aligned upper andflower tubular portions v3 and 4 separatedby a slot arranged to receivethe board to be tested, said portions being con nected at one side by a wing jand the upper portion 3 of the block b'ein'g'alsor` provided diametrically opposite the wing 5., with a wing 6 for convenience of manipulation in using the tool. The upper end of the 'shank 1 is threaded to engage the interiorlythread i ed 'centralportion of an operating sleeve 7, they lower portion of which latter 'is bored smooth to slidinglyengage' the lower portion of the shank. the shank being provided vwith a scale A adaptedto be' read in connection 4 with the lower end of thev sleeve. This scale is graduated so asto give indica-tions corresponding to 'those afforded' by machines known in the yart and" which 'nominally eX- press in pounds per square inch the pressure required to puncture or burst a sheet of pa Der' or paper board.` 4lnasmucliasv the tool herein described is intendedfor testin'gfpa-per board ofsubstantial thickness and strength, the graduationsbeginwith an indication of 200. that is, nominally, fa bursting strength of twohundred pounds per square inch. y

Slidingly arrangedo'nnthe graduated portion of the shank l lis ank indicating collar y,

2O 'formed with an internalannulargrecess n iiiwhich is arranged a split claspingspring 21'@ b v means or which it is yieldingly and it may beseton the shank. n

' vTn the upper endA or ,the sleeve 7v is arranged a threaded tubular connecting plug frictioiiallv held iiiv any position to `which '8, v.the upper fend of which extends'abo've the top of the sleeve and'carries awinged op erating nut 9. .l i g Theplug 8 is formed withan oriiced ciosspartition 10 slidinglyengaged bythe headed upperend ofa stern 11 to'the'lower y end oi which latter is secured`v in the presont instance through screwy threaded engagement a plunger head 12. This plunl ger head (see Fig. 4) is formed with a top flange 12a slidingly engaging the inner wall of the shank 1 and a wedge-shaped die 12b, formed with two parallel ridges on its bearing face at the lower end of the central body, marked 12, and this central portion makes sliding, but non-rotatable engagement with a bushing 14 secured in the portions of the base block of the tool, a

pin 15 secured to the bushing and engaging a longitudinal groove in the plungerblock 12 being employed for the purpose in the present instance. The plunger head is arranged to seat solidly against and serve as a lock nut for a split thrust collar 16 which makes tight frictional screw threaded engagement with the stem 11, and intermediate this collar and athrust collar 17 which bears against a ball-bearing support yhoused in the. tubular connecting plug 8 below the partition 10 is arranged a helical compression spring 18 surrounding said stem. A cross pin 13 is employed for further security in holding the plunger head on the stein.

The portion t of the base block is threaded in axial alignment with the shank and plunger stem to receive a plug 19 which is milled around its base to enable it to be readily turned so as to clamp a sheet of the board tobe tested between its annular upper face and theklower face of the portion 3 ofthe base block. This plug is recessed or oriiced as shown to provide a cavity in alignment with the plunger die. The periphery of the plug .is provided with a micrometer scale B arranged to be read in connection with an indicator line adjacent thereto on the base block, so as togive an indication expressed in thousandths of an inch of the thickness of a board clamped in the tool in readiness for a test of its bursting strength.

In assembling the parts, the operating sleeve 7 and connecting plug 8 are connected and the stemris inserted in the connecting plug, and the parts of the ball bearing, the spring and the retaining members at the lower end of the stem then assembled, the thrust collar. being screwed upon the stem as near as may be to a point where the spring will. be coniined under a pressure somewhat below the stress required to give .an indication of 200 pounds on the scale on the-shank,sa v a stress equivalent to an indication of 180. The operating. sleeve is now screwed `down upon the shank until the reading'of the scale is 200 pounds. in which position, if the adjustment should chance to be correct the plunger top should be lifted somewhat above the partition 10 when the bottom of the plunger die is sustained at a level with the plane ot' the lower face ot the base block part 3,-that is, the plane of the upper face ot' a piece of board clamped in position for a test,see Fig. 2. By ineans ot a suitable apparatus (which. forms no part of this invention and therefore need not be described) the stress of the spring at this compression is now determined, and any needed adjustment' of the operating sleeve up or down on the connecting plug to attain this relationship of the parts may be made by turning the sleeve with reference to the barrel in the proper direction and to the required extent, the pitch of the threaded connection and its effect upon the adjust ment being known. When the exact adjustment of the graduation is attained the operating nut is seated as tightly as possible against the operating sleeve on the connecting plug to secure the parts against change. The high initial tension of the spring enables the plunger die to be lifted out of engagement with the material being tested after .the completion of a test and shortly after the operating sleeve has been unscrewed past the 200 pounds indication, which would not be possible were the initial tension low.

The manner in which my novel testing device is used requires `but brief explanation. The operating sleeve is lunscrewed to lift the die high enough to clear the opening below the base block member S-if it was not left in such position at the close of a previous tesa-and the board to be tested. inserted in such opening and clamped in place, the micrometer scale giving an indication of its thickness. The operating handleor nutis then turned, compressing the spring until its stress causes it to burst through the board. and giving an indication on the scale A. The collar 20 may have been arranged in Contact with the lower end of the operating sleevel before beginning to screw the nut and sleeve. down, in which oase its upper edge will retain the indication after the sleeve has been screwed upwardly again, or suchnut may be lifted into contact with the sleeve from lowermost positionafter the die has broken through the board and before unscrewing theL sleeve and the clamping plug 19 to disengage the materiahif for any reason it should be more convenient to remove the tester from the board for subsequent reading than read it at once from the edge of the sleeve.

1c vA testing device of the character described and comprising a shank. trans verselvslotted base block. a springfstressed plunger. slidingly Amounted in said shank and provided with means for indicating the stress of the spring, and a recessed clamping plug in alignment with said plunger, said plug being provided with a scale indicating the distance between the opposed clamping faces.

2. A testing device of the character described and comprising a'shank, a transversely slotted hase block, a spring-stressed plunger slidingly mounted in said shank and provided with means for` indicating the stress of the spring, and a recessed clamping plug in alignment with said plunger, said clamping plug being screw-threaded and provided with a micrometer scale.

3. A testing device of the character described and comprising a shank, a transversely slotted base block, a plunger member slidingly mounted vin said shank and equipped witha plunger point, a spiral compression spring arranged to bear against said plunger VVAmember, an 4operating sleeve having screw threaded connection with said shank and arranged to cooperate with said spring, said base block and operating sleeve both beingfprovided with winged manipulating members.'

4. A testing device of the character described and comprising a base member arranged tol support the board to be tested, a shankpan operating sleeve having screw threaded: connection with said shank, said shank and ysleeve being one or the other u marked with a scale of graduation indicating their relative movement, a connecting plug secured'to said sleeve and longitudinally adjustable with respect thereto, a plunger member having a headed stem slidingly engaging said connecting plug and at its lower end provided with a thrust collar, and a spiral compression spring compressed to a relatively high initial tension betweensaid connecting plug and thrust collar.

5. A testing device according to claim ety in which said connecting plug is a tubular externally screw-threaded member making threaded engagement with Said operating sleeve and in which a Winged lock nut is arranged to secure said sleeve and plug together in adjusted relation.

6. A testing device according to claim 4 in which said shank is threaded above said graduations and the lower part ofsaid operating sleeve is cylindrical' and slidingly engages the graduated portion of said shank. .7. A testingdevice according to claim 4 in which said operating sleeve is formed with a smooth cylindrical 'interior at its lower portion and a threaded interior above saidl smooth portion, the lower end of said threaded portion being arranged to cooperate with said shank and the upper end arranged to engage said connecting plug.

JOHN W. WEBB. 

